You may use a workaround with a hidden numeric question. It is not as comfortable as with the default input with other, but maybe it is good enough.
1) add a new question directly after the option list question
2) question type for this new question is numerical input. There you can define a maximum.
3) in the option list question:
a) option 'other' -> off
b) add this code to the questiontext (with click on Source):
Code:
<script type="text/javascript" charset="utf-8">
$(document).ready(function() {
// Identify the questions
var q1 = $('#question'+{QID}+'');
var q2 = $(q1).nextAll('.numeric:eq(0)');
// Hide the numeric question
$(q2).hide();
// Move the hidden numeric input into the option list
$('.label-text:last', q1).append($('input', q2));
// Some styling...
$('input', q1).css({
'width': '20%',
});
});
</script>
c) in the 'edit answer options' add your text in the third option ("Yes, several times:")
Should work with 2.50 and at least the default template.
Edit: I guess you have to mention in the question text or anywhere else, that there is a maximum for the input.